1. Field of the Invention
This invention generally relates to a drain cover assembly for a sink, and more specifically, to a drain cover having an upper basket member threadably interconnected with a lower plug member positioned within a sink drain pipe, the drain cover assembly capable of being opened and closed by rotating the basket with respect to the plug.
2. Related Art
Sinks are used in industrial and residential applications and drain covers are a necessary component of these sinks. Drain covers have two basic functions. The first function is to stop liquid from draining thus allowing the sink to be filled with liquid. The second function is to open the sink to allow while acting as a strainer to prevent solid material from being drawn down the drain.
Sink drain cover assemblies generally include a basket strainer having a plurality of holes and a strainer post extending up therefrom. A stopper, which fits within the sink drain pipe opening, may be mounted on a lower portion of the post. The basket strainers of this type are adapted to be opened and closed manually by manipulating the post, so as to align bulges in the post with slots in the basket in order to raise and lower the post, and hence the stopper, with respect to the basket, permitting draining and filling of the sink.
Alternatively, the basket itself may close off the drain, the post coacting with a bridge member in the drain pipe of the sink to maintain the basket off the drain or to allow the basket to move down against the drain. Such a drain basket generally includes a rubber gasket mounted on the underside of the basket. These basket covers generally rely on the weight of the water in the sink to push the gasket on the basket against the drain opening to prevent water from draining from the sink. It has been found, however, that the weight of the water in the sink sometimes does not create enough downward force to provide a leakproof seal, and accordingly, there may be some leakage by such prior art basket strainers. Both types of drain cover assemblies have baskets with a central post which makes cleaning difficult and time consuming. To clean these baskets, one has to remove the basket from the drain. If the sink is not fully drained, this can result in solid materials flowing down the drain which can lead to subsequent problems that may require the need of a plumber.
Accordingly, what is needed, and has not heretofore been provided, is a drain cover assembly which can stop a sink and which can also strain solid material from a liquid draining from a sink, and which can be opened and closed by rotating the basket portion with respect to a plug portion. Additionally, what is needed is a plug with apertures to prevent solid material from escaping down the drain pipe when the basket is removed. Additionally, it would be beneficial to have a basket with depressions for gripping so as to make the basket easily to grasp and rotate, and to have a basket which is shaped to facilitate easy cleaning, and which has a plug which is shaped so as to fit drain pipes of varying sizes.
Previous efforts to create sink drain cover assemblies include:
Liu, U.S. Pat. No. 5,535,455, discloses a sink strainer for a garbage disposal unit which includes a strainer unit, a seat and a mounting flange. The strainer unit includes a handle (11) which extends up from the strainer member. The strainer member (12) which is interconnected with a plug member (13), has a plurality of openings spaced thereabout. The plug member has a platform and a surrounding wall that depends therefrom. Multiple slope guides are contained in the surrounding wall. The strainer member interconnects with the plug member by means of threaded engagement of the handle. Mounting flanges are adapted to fit into a conventional sink. A limiter on the seat coacts with the slope guide to interconnect the strainer member with the seat. The seat is inserted into the mounting flange. When the limiter is inserted into the slope guide and turned, the plug member is forced to go down to seal the drain closed, while turning the plug in a counter direction allows the plug to move upward with respect to the limiter to produce a gap, resulting in an open position making drainage possible.
Martin, U.S. Pat. No. 5,369,815, discloses a sink strainer having a hollow strainer body with an open upper end and a tubular outlet at a lower end. A basket strainer is mounted in the upper end and a tubular outlet at a lower end. A basket is mounted in the upper end. The basket strainer has a bottom wall with a valve stem guide. A valve stem extends through the guide and a handle is secured to an upper end of the valve stem. An outlet member is positioned below the strainer body having screw threaded portion for engagement with a lower end of the valve stem. An annular valve member is secured to the valve stem below the basket strainer. When the stem valve handle is turned on the handle in the opposite direction the annular valve member is raised off the annular valve seat, and when the valve stem is turned on the handle in the opposite direction the valve member and its annular seal will move downwardly against the annular valve seat.
Watts, U.S. Pat. No. 4,720,877, discloses a drain closure having a stopper mounted to slide up and down on a post threaded into the bottom of a strainer body. The post includes a spring which expands against the internal surface of the stopper to provide frictional force to hold the stopper in place. When the stopper is pulled upwardly to an open position it is held open by the frictional force. The stopper can be pushed down to a closed position by foot or hand pressure in which case the spring helps to maintain the stopper in a closed position.
Westgerdes, U.S. Pat. No. 4,586,203, discloses a sink strainer assembly including a strainer body having a threaded bore, a strainer basket having a bottom wall formed with a bore, a post formed with a top handle, a bottom threaded portion and a reduced diameter middle portion, and a rubber stopper having a bore of the same diameter as the middle portion of the post. The strainer basket is mounted to the post and the rubber stopper is forced over the threaded bottom of the post and sits within the middle portion contacting the underside of the strainer. The strainer basket, post and stopper can be inserted as a unit into the strainer body where the threaded bottom portion of the post meets with the threaded bore of the strainer. The post is rotatable to lower the rubber stopper into sealing engagement with the annular shoulder to close the drain, or to raise the rubber stopper to open the drain.
Hamburg, U.S. Pat. No. 3,813,708, discloses a kitchen sink strainer and drain unit including a drain bowl passing within a drain opening of the sink having a keyhole slot opening in the bottom. A wedge shape cam is formed around the opening on the bottom surface of the drain bowl. A strainer is nested in the drain bowl and has a central stem extending from the strainer through the keyhole slot with a radical projection engaged with the cam beneath the drain bowl to seal the strainer downwardly against the drain bowl interior wall. A spring surrounding the stem forces the strainer upwardly for spacing the strainer from the drain bowl for opening the drain or drainage when the strainer is rotated to disengage the projection from the cam. A hand grip is formed across the interior of the strainer to allow for grasping and rotating the strainer.
Richards, U.S. Pat. No. 3,802,001, discloses a basket assembly for a sink strainer having a stem with a lower end having a pilot element to project through the strainer body with thread means positioned above the pilot element. The threaded portion provides a platform for engaging the basket to advance the basket to seat the basket against the drain, and on the other hand, to provide a ledge adapted to support the basket against a slot in the drain to maintain the drain in an open position. The stem includes an upper end extending through the strainer for grasping.
Bergin, U.S. Pat. No. 3,800,339, discloses a sink stopper mounted on a drain of a sink having a threaded step. A plug which is part of the stopper is threaded over the top of the stem and is moveable from a closed position in which the plug engages an annular member to plug the fluid opening, to an open position in which the plug is spaced from the annular member to permit fluid flow.
Politz, U.S. Pat. No. 3,777,320, discloses a drain having a drain body with a flange for support in a sink opening, a reduced drain outlet section with a downwardly opened threaded section provided at upper end with a beveled section so that the open portion can be guided over a spud to close off the drain to retain liquid in the sink. A stem extends up from the basket for grasping the device.
Leavens, U.S. Pat. No. 4,320,540, disclosed a discharge drain assembly including a drain body and a plug adapted to fit in the drain. The plug includes a stainless steel strainer with a hollow knob. The knob retains a slotted head of a spindle. The spindle has a neck for receiving a sealing washer and a lower portion with three legs which support the plug in an opened position and restrain rotation in a first direction beyond the open position. The leg portions also cam the plug to a closed position when rotated in a direction opposite to the first direction.
Taylor, Jr., et al., U.S. Pat. No. 4,683,597, discloses a drain plug comprising threaded bolt extending through a rubber washer. The bolt is screwed into a tapped hole in a shoe assembly of the drain providing a secure plug.
Young, U.S. Pat. No. 2,890,463, discloses sink strainer having a hollow body with an outlet portion on a lower end having a valve seat and a cup for allowing liquid to drain therefrom. A handle can be used to move the cup up and down with respect to the valve seat to open and close the device.
The citation of any reference herein should not be deemed an admission that such reference is available as prior art to the invention. None of these previous efforts disclose all of the benefits of the present invention, nor do these previous patents teach or suggest all the elements of the present invention.